(2014/12/11 12:35), Qiu, Michael wrote: > On 12/11/2014 11:12 AM, Tetsuya Mukawa wrote: >> Hi Michael, >> >> (2014/12/09 23:39), Qiu, Michael wrote: >>> On 2014/12/9 14:32, Tetsuya Mukawa wrote: >>>> The patch adds rte_eth_dev_save() and rte_eth_dev_get_changed_port(). >>>> rte_eth_dev_save() is used for saving current rte_eth_dev structures. >>>> rte_eth_dev_get_changed_port() receives the rte_eth_dev structures, then >>>> compare these with current values to know which port is actually >>>> attached or detached. >>>> >>>> Signed-off-by: Tetsuya Mukawa <mukawa at igel.co.jp> >>>> --- >>>> lib/librte_ether/rte_ethdev.c | 21 +++++++++++++++++++++ >>>> lib/librte_ether/rte_ethdev.h | 21 +++++++++++++++++++++ >>>> 2 files changed, 42 insertions(+) >>>> >>>> diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c >>>> index 51697e1..6a3700e 100644 >>>> --- a/lib/librte_ether/rte_ethdev.c >>>> +++ b/lib/librte_ether/rte_ethdev.c >>>> @@ -416,6 +416,27 @@ rte_eth_dev_count(void) >>>> return (nb_ports); >>>> } >>>> >>>> +void >>>> +rte_eth_dev_save(struct rte_eth_dev *devs) >>>> +{ >>>> + if (devs == NULL) >>>> + return; >>>> + >>>> + /* save current rte_eth_devices */ >>>> + memcpy(devs, rte_eth_devices, >>>> + sizeof(struct rte_eth_dev) * RTE_MAX_ETHPORTS); >>>> +} >>>> + >>>> +int >>>> +rte_eth_dev_get_changed_port(struct rte_eth_dev *devs, uint8_t *port_id) >>>> +{ >>>> + /* check which port was attached or detached */ >>>> + for (*port_id = 0; *port_id < RTE_MAX_ETHPORTS; (*port_id)++, devs++) >>>> + if (rte_eth_devices[*port_id].attached ^ devs->attached) >>>> + return 0; >>> Can we have more than one port changed? >>> If so, your logic should do little modify. >> The port hotplug APIs cannot attach or detach multiple port at the same >> time. > What I mean is can we first detach one port, then another? If it legal > to do this, here will always return the port with the min port_id.
It's not legal. Above 2 functions are implemented to be called by rte_eal_dev_attach(). When rte_eal_dev_attach() is called, rte_eth_dev_save() and rte_eth_dev_get_changed_port() will be invoked continuously in the function. But while executing the 2 functions, only one port status will be changed, because rte_eal_dev_attach() and rte_eal_dev_detach() should be called one by one. Thanks, Tetsuya > > Thanks, > Michael >> And the APIs are not thread safe. DPDK application should have lock >> properly if multiple threads call the APIs. >> Because of this, we don't need to take care of such a case. >> >>> Thanks, >>> Michael >>>> + return 1; >>>> +} >>>> + >>>> static int >>>> rte_eth_dev_rx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues) >>>> { >>>> diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h >>>> index b329e11..03c8850 100644 >>>> --- a/lib/librte_ether/rte_ethdev.h >>>> +++ b/lib/librte_ether/rte_ethdev.h >>>> @@ -1642,6 +1642,27 @@ extern struct rte_eth_dev rte_eth_devices[]; >>>> extern uint8_t rte_eth_dev_count(void); >>>> >>>> /** >>>> + * Function for internal use by port hotplug functions. >>>> + * Copies current ethdev structures to the specified pointer. >>>> + * >>>> + * @param devs The pointer to the ethdev structures >>>> + */ >>>> +extern void rte_eth_dev_save(struct rte_eth_dev *devs); >>>> + >>>> +/** >>>> + * Function for internal use by port hotplug functions. >>>> + * Compare the specified ethdev structures with currents. Then >>>> + * if there is a port which status is changed, fill the specified pointer >>>> + * with the port id of that port. >>>> + * @param devs The pointer to the ethdev structures >>>> + * @param port_id The pointer to the port id >>>> + * @return >>>> + * - 0 on success, negative on error >>>> + */ >>>> +extern int rte_eth_dev_get_changed_port( >>>> + struct rte_eth_dev *devs, uint8_t *port_id); >>>> + >>>> +/** >>>> * Function for internal use by dummy drivers primarily, e.g. ring-based >>>> * driver. >>>> * Allocates a new ethdev slot for an ethernet device and returns the >>>> pointer >>